U.S. patent number 9,238,126 [Application Number 13/439,534] was granted by the patent office on 2016-01-19 for biofeedback controlled deformation of sinus ostia.
This patent grant is currently assigned to SANOVAS INC.. The grantee listed for this patent is Lawrence J. Gerrans, Erhan H. Gunday. Invention is credited to Lawrence J. Gerrans, Erhan H. Gunday.
United States Patent |
9,238,126 |
Gerrans , et al. |
January 19, 2016 |
Biofeedback controlled deformation of sinus ostia
Abstract
A method of dilating a paranasal sinus ostium of a patient,
which includes inserting a catheter having at least one balloon
into a sinus ostium having an ostial wall, inflating the balloon by
supplying fluid thereto such that the balloon exerts a force on the
ostial wall, determining at least one parameter of the balloon,
establishing an amount the balloon can be inflated without
fracturing the sinus ostium based at least in part on the
determined parameter of the balloon, and dilating the sinus ostium
by inflating the balloon to an amount that does not exceed the
established amount.
Inventors: |
Gerrans; Lawrence J. (San
Anselmo, CA), Gunday; Erhan H. (Great Neck, NY) |
Applicant: |
Name |
City |
State |
Country |
Type |
Gerrans; Lawrence J.
Gunday; Erhan H. |
San Anselmo
Great Neck |
CA
NY |
US
US |
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Assignee: |
SANOVAS INC. (Sausalito,
CA)
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Family
ID: |
46966630 |
Appl.
No.: |
13/439,534 |
Filed: |
April 4, 2012 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20120259217 A1 |
Oct 11, 2012 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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61473448 |
Apr 8, 2011 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M
29/02 (20130101); A61M 25/1011 (20130101); A61B
17/24 (20130101); A61M 25/10181 (20131105); A61M
25/10184 (20131105); A61M 25/10186 (20131105); A61M
2025/1052 (20130101); A61B 6/501 (20130101); A61M
2025/109 (20130101); A61B 6/12 (20130101); A61M
2025/1086 (20130101) |
Current International
Class: |
A61M
29/02 (20060101); A61B 17/24 (20060101); A61B
6/00 (20060101); A61B 6/12 (20060101); A61M
25/10 (20130101) |
Field of
Search: |
;600/116,204
;606/199 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Kuhn, F., et al.; "Balloon catheter sinusotomy: One-year
follow-up-Outcomes and role in functional endoscopic sinus surgery"
Otolaryngol Head Neck Surg 2008; 139: S27-S37. cited by applicant
.
Weiss, R., et al.; "Long-term outcome analysis of balloon catheter
sinusotomy: Two-year follow-up" Otolaryngol Head Neck Surg 2008;
139: S38-S46. cited by applicant .
Bolger, W., et al.; "Safety and outcomes of balloon catheter
sinusotomy: A multicenter 24-week analysis in 115 patients"
Otolaryngol Head Neck Surg 2007; 137: 10-20. cited by
applicant.
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Primary Examiner: Le; Long V
Assistant Examiner: Weatherby; Ellsworth
Attorney, Agent or Firm: St Onge Steward Johnson and Reens
LLC
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims the benefit under 35 U.S.C.
.sctn.119(e) of the U.S. Provisional Patent Application Ser. No.
61/473,448 filed on Apr. 8, 2011, the content of which is
incorporated by reference herein in its entirety.
Claims
What is claimed is:
1. A method of dilating a paranasal sinus ostium of a patient, the
method comprising the steps of: inserting a catheter having at
least one balloon into a sinus ostium of a patient, the sinus
ostium having an ostial wall; determining the balloon type;
inflating the balloon by supplying fluid thereto such that the
balloon exerts a force on the ostial wall without fracturing the
sinus ostium; after the balloon is inflated in the sinus ostium,
determining a diameter of the inflated balloon; while the balloon
is inflated in the sinus ostium, calculating a threshold amount to
which the balloon can be inflated that will not fracture the sinus
ostium of the patient using the determined inflated balloon
diameter and setting the threshold amount in a pump having a
sensor; monitoring the increasing diameter of the balloon while
repeatedly deflating and inflating the balloon by supplying fluid
to the balloon in a pulsed fashion; and using the pump having a
sensor to monitor the diameter to determine when to stop inflation
of the balloon to an amount that does not exceed the threshold
amount.
2. The method of claim 1, wherein the step of inflating the balloon
comprises supplying fluid to the balloon and the pump comprises an
electro-pneumatic pump and the balloon diameter is determined by
using at least one measurement made by the electro-pneumatic
pump.
3. The method of claim 1, wherein the step of determining the
balloon type comprises connecting the catheter to a balloon
identification plate, and connecting said identification plate to
the pump, the pump comprising an electro-pneumatic pump that
supplies fluid to the balloon during the step of inflating the
balloon.
4. The method of claim 3, wherein the step of detecting further
comprises orienting the identification plate with a key.
5. The method of claim 3, wherein the pump identifies the balloon
from the balloon identification plate electro-mechanically.
6. The method of claim 3, wherein the pump identifies the balloon
from the balloon identification plate electro-optically.
7. The method of claim 3, wherein the pump includes balloon profile
data corresponding to the balloon, and a processor that controls
the supply of fluid to the balloon based at least partially on the
balloon profile data.
8. The method of claim 7, wherein the processor interprets the
balloon profile data and displays a multi dimensional image of the
ostium based at least partially on the balloon profile data.
9. The method of claim 7, wherein the pump further includes an
imaging system that can translate data from at least one imaging
modality disposed in the catheter.
10. The method of claim 8, wherein the processor further interprets
direct and/or indirect imaging data and the multi-dimensional image
of the ostium is based on the direct and/or indirect imaging
data.
11. The method of claim 1, further comprising the step of advancing
a distal end of a guide device to a desired location in the
paranasal sinuses before inserting the catheter, wherein the
catheter is inserted into the sinus ostium by advancing the
catheter over said guide device.
12. The method of claim 11, further comprising the step of removing
the guide device from the paranasal cavity before inflating the
balloon.
13. The method of claim 1, wherein the balloon has an outer wall
with an abrasive surface such that the repeated deflation and
inflation causes the abrasive surface to resect biological material
in the sinus ostium.
14. The method of claim 13, wherein the biological material
comprises polyps.
15. The method of claim 13, wherein the biological material
comprises tumors.
16. The method of claim 13, wherein the biological material
comprises edematous tissue.
17. The method of claim 1, further comprising the step of
delivering a therapeutic and/or diagnostic agent to the ostium via
a delivery lumen of the catheter.
18. The method of claim 17, wherein the step of delivering the
therapeutic and/or diagnostic agent to the ostium comprises
delivering the agent through at least one opening in the catheter
in fluid communication with the delivery lumen.
19. The method of claim 17, wherein the balloon has an outer wall
with an abrading surface such that the repeated deflation and
inflation causes the abrading surface to abrade biological material
in the sinus ostium.
20. The method of claim 19, wherein a wall of the at least one
balloon has at least one opening in fluid communication with the
delivery lumen, and the step of delivering the therapeutic and/or
diagnostic agent to the biological material comprises delivering
the agent through said at least one opening and inflating said at
least one balloon until it contacts said biological material.
21. The method of claim 17, wherein the therapeutic and/or
diagnostic agent comprises an antimicrobial agent.
22. The method of claim 17, wherein the therapeutic and/or
diagnostic agent comprises an anti-inflammatory agent.
23. The method of claim 17, wherein the therapeutic and/or
diagnostic agent comprises a vasoconstrictor.
24. The method of claim 17, wherein the therapeutic and/or
diagnostic agent comprises a mucolytic agent.
25. The method of claim 17, wherein the therapeutic and/or
diagnostic agent comprises an anti-histamine.
26. The method of claim 17, wherein the therapeutic and/or
diagnostic agent comprises an anti-cholinergic agent.
27. The method of claim 17, wherein the therapeutic and/or
diagnostic agent comprises a diuretic.
28. The method of claim 1, wherein the step of inflating the
balloon comprises supplying fluid to the balloon with the pump, the
pump comprising a hand or foot actuated pump and the balloon
diameter is determined by using at least one measurement made by
the hand or foot actuated pump.
29. The method of claim 1, wherein the step of inflating the
balloon comprises supplying fluid to the balloon with the pump, the
pump comprising a pneumo-mechanical pump and the balloon diameter
is determined by using at least one measurement made by the
pneumo-mechanical pump.
30. The method of claim 1, wherein the step of inflating the
balloon comprises supplying fluid to the balloon with the pump, the
pump comprising an electro-mechanical pump and the balloon diameter
is determined by using at least one measurement made by the
electro-mechanical pump.
31. The method of claim 1, wherein the catheter includes at least
one imaging marker.
32. The method of claim 1, further comprising the steps of
measuring the fluid flow rate as fluid is supplied to the balloon
and using the measured fluid flow rate to determine the diameter of
the inflated balloon.
Description
FIELD OF THE INVENTION
The present invention relates to balloon catheters and methods of
using such catheters for treating conditions of the nose, nasal
cavities and paranasal sinuses. More specifically, the present
invention relates to methods utilizing balloon catheters for
dilating the sinus ostia, resecting biological material and
delivering therapeutic and/or diagnostic agents within the nose,
nasal cavities and paranasal sinuses.
BACKGROUND OF THE INVENTION
The removal of unwanted and/or life threatening biological material
from interior portions of bodily cavities, such as organs, vessels,
articular joints and structures, sinuses, and various bodily
lumens, is a very common procedure in various medical specialties
and disciplines, such as pulmonology, cardiology, urology,
gynecology, gastro-enterology, neurology, otolaryngology,
orthopedics, and general surgery. Recently, balloon catheters have
been employed to release sinus congestion. Accordingly, various
instruments and methods have been employed to perform these
procedures, which are generally well known in the art.
The nasal cavity (or nasal fossa) is a large air filled space above
and behind the nose in the middle of the face. The floor of the
nasal cavity, which forms the roof of the mouth, is made up by the
bones of the hard palate: the horizontal plate of the palatine bone
posteriorly and the palatine process of the maxilla anteriorly. To
the front of the nasal cavity is the nose, while the back blends,
via the choanae, into the nasopharynx.
The paranasal sinuses are hollow cavities in the skull connected by
small openings, known as ostia, to the nasal canal. Each ostium
between a paranasal sinus and the nasal cavity is formed by bone
covered by a layer of mucosal tissue. Normally, air passes into and
out of the paranasal sinuses through the ostia and into the nasal
canal.
The paranasal sinuses include the maxillary sinuses, the frontal
sinuses, the ethmoid sinuses, and the sphenoid sinuses. The
maxillary sinuses are also called the maxillary antra and are the
largest of the paranasal sinuses. They are located under the eyes,
in the maxillary bones. The frontal sinuses are superior to the
eyes, in the frontal bone, which forms the hard part of the
forehead. The ethmoid sinuses are formed from several discrete air
cells within the ethmoid bone between the nose and the eyes. The
sphenoid sinuses are in the sphenoid bone at the center of the
skull base under the pituitary gland. Sinusitis is an inflammation
of the sinus lining commonly caused by bacterial, viral and/or
microbial infections; as well as, structural issues such as ostial
blockage. Symptoms include nasal congestion, facial discomfort,
nasal discharge, headache, and fatigue. Sinusitis can be considered
acute (last 4 weeks or less) or chronic (12 weeks or longer).
Sinusitis affects 29.3 million people each year, making it one of
the most common health problems in the U.S. according to the U.S.
Department of Health and Human Services, Centers for Disease
Control and Prevention National Center for Health Statistics,
Summary Health Statistics for U.S. Adults: National Health
Interview Survey, 2009 (2010). It is responsible for great
healthcare expenditures and a significant loss of workplace
activity.
Another common ailment affecting the nose and paranasal sinuses is
nasal polyps. Nasal polyps are benign masses that grow from the
lining of the nose or paranasal sinuses. Nasal polyps often result
from chronic allergic rhinitis or other chronic inflammation of the
nasal mucosa. Nasal polyps are also common in children who suffer
from cystic fibrosis. In cases where nasal polyps develop to a
point where they can obstruct normal drainage from the paranasal
sinuses, they can cause sinusitis.
Various drugs have been used to treat sinusitis, including
antibiotics and corticosteroid sprays. However, with the use of
intranasal sprays, most of the spray does not actually enter the
affected sinuses. Accordingly, introduction of drugs directly into
the sinuses has been proposed. For instance, U.S. Pat. No.
7,361,168 to Makower et al. discloses implantable devices that may
be positioned within a naturally occurring or man-made cavity or
passageway in a nostril, nasal cavity, sinus, etc. via balloon
catheters.
Functional Endoscopic Sinus Surgery (FESS) is the most common
surgical procedure for clearing blocked sinuses. However, the
procedure involves removing bone and tissue, which can lead to
post-operative pain, scarring and bleeding. The use of balloon
catheters in sinus surgery can minimize or eliminate many of these
drawbacks.
One method involves creating a new opening from a sinus into the
nose to dilate a sinus ostium or duct, or to excise a sinus. U.S.
Pat. No. 7,854,744 to Becker discloses methods of performing
balloon catheter astronomy of the maxillary ostium, middle meatal
maxillary ostium, and inferior meatal ostium and a method of
performing ethmoidectomy of the anterior ethmoid sinus, posterior
ethmoid sinus, and sinusotomy of the frontal sinus. The methods
generally involve pushing a balloon catheter through the ostia into
the desired sinus cavity, inflating the balloon to 9 bar for 20
seconds, and deflating the balloon. This may be repeated. After
final deflation, the catheter is removed from the enlarged ostium.
The catheters employed by Becker utilize stainless steel catheters
with radia of 0.13 inches, length of 4 to 10 inches, and wall
thickness of at least 0.035 inches. The catheter tip contains a
curved distal tip with an angle of 70.degree. to 180.degree.. The
distal tip contains a balloon formed of polyethylene terephthalate
with a length of 4 mm to 30 mm and working inflated diameter of 2
mm to 15 mm. The balloon has a distal neck and distal tapered
region that is adhered to the distal tip of the catheter using an
adhesive, such as cyanoacrylate.
In at least some procedures wherein it is desired to position a
balloon catheter in the ostium of a paranasal sinus, it is
necessary to advance the balloon catheter through complicated or
tortuous anatomy in order to properly position the balloon catheter
within the desired sinus ostium. Also, there is a degree of
individual variation in the intranasal and paranasal anatomy of
human beings, thus making it difficult to use the stiff-shaft
preshaped balloon catheters of Becker for use in all individuals.
The Becker patent describes the necessity of having available a set
of balloon catheters, each having a particular fixed angle so that
the physician can select the appropriate catheter for the patient's
anatomy.
Accordingly, a series U.S. Patents to Chang et al. (e.g. U.S. Pat.
No. 7,727,226) disclose methods utilizing flexible balloon catheter
devices for use in ENT procedures. Exemplary methods for improving
drainage from a paranasal sinus that has a natural ostium comprise
inserting a guidewire to a position near the ostium, using the
guide to advance a balloon catheter within the ostium and using the
balloon to dilate the natural ostium. A sizing balloon situated
around the dilating balloon may be inflated using an imageable
inflating medium, such as saline with radioopaque contrast agent or
carbon dioxide gas. The distal region of the sizing balloon is
imaged to enable the operator to estimate the size of the
anatomical opening or the diameter of the narrowest region in a
tubular anatomical region. Chang et al. also provide methods for
treating mucocysts or other flowable substance containing
structures located in the sinus by penetrating the structure,
compressing the structure with, for example, the balloon of a
balloon catheter to force the contents out of the opening formed by
the penetrator, advancing the penetrator into the sinus and opening
in the cyst, and positioning the balloon in the sinus using the
balloon to force the contents out of the opening formed by the
penetrator.
A common risk, however, with the above described methods and
apparatus is the possibility of under or over-inflation of the
balloon portion of the catheter. In the case of under-inflation,
the effect of the catheterization on the ostium may be insufficient
and therefore require additional treatments, adding to procedure
times and increasing the risk of complications. In the case of
over-inflation, the balloon catheter can fracture the ostium,
leading to restenosis.
Imaging modalities, such as those used with a sizing balloon,
cannot assess information regarding pressure or volume of inflated
balloons. Variation in constriction responses associated with the
nature of an obstruction highlight the importance of control over
dilation set-points such as the rate of dilation, pressure, volume
and the diameter of the inflated balloon. Many patient maladies are
simply not remedied by these procedures because the methods are not
efficient, safe, and reproducible, and/or the instruments employed
lack the appropriate physiological measurement and/or feedback
necessary to ensure the safety, efficacy, and reproducibility of
the procedure.
Further, simple pressure control means, such as those described in
US 2003/0105483 to Hudson et al., are not optimal because they only
involve controlling pressure to a pre-set level through valve caps.
The pre-set can prevent extreme over-inflation, but requires the
user to approximate a pre-set value and does not allow for real
time monitoring and feedback as the balloon is within a nasal or
paranasal lumen. The pre-set also does not account for
under-inflation when the diameter of an ostium is larger than
anticipated.
Hence, there is a significant need for systems and methods for
deforming the sinus ostia that are capable of accurately and
directly determining in vivo the size and optionally the compliance
of areas of the nose, nasal cavities, and paranasal sinuses, such
as the ostia. Such systems and methods should be relatively simple
to accommodate a single-use strategy.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide
methods for deforming sinus ostia that allow the ostia to deform
without fracture.
It is also an object of the present invention to remove biological
matter from the paranasal sinuses using a balloon catheter without
fracturing the ostia.
It is a further object of the present invention to deliver
diagnostic and/or therapeutic agents to the paranasal sinuses
without fracturing the ostia.
In order to overcome the deficiencies of the prior art and to
achieve at least some of the objects and advantages listed, the
invention comprises a method of dilating a paranasal sinus ostium
of a patient. The method includes inserting a catheter having at
least one balloon into a sinus ostium having an ostial wall;
inflating the balloon by supplying fluid thereto such that the
balloon exerts a force on the ostial wall; determining at least one
parameter of the balloon; establishing an amount the balloon can be
inflated without fracturing the sinus ostium based at least in part
on the determined parameter of the balloon; and dilating the sinus
ostium by inflating the balloon to an amount that does not exceed
the established amount.
In some embodiments, the at least one parameter is the pressure of
the balloon. In other embodiments, the at least one parameter
comprises the volume of the balloon. In yet other embodiments, the
at least one parameter is the diameter of the balloon.
In certain embodiments, the method further comprises repeating the
steps of determining at least one parameter of the balloon,
establishing an amount the balloon can be inflated without
fracturing the sinus ostium, and dilating the sinus ostium by
inflating the balloon.
In certain advantageous embodiments, the step of inflating the
balloon comprises supplying fluid to the balloon with a hand or
foot actuated pump and the at least one parameter of the balloon is
determined by using at least one measurement made by the hand or
foot actuated pump. In some of these embodiments, the method
further comprises detecting a balloon type for the catheter
inserted into the bodily cavity before inflating the balloon,
wherein the step of determining at least one parameter of the
balloon is based at least partially on the balloon type
detected.
In certain advantageous embodiments, the step of inflating the
balloon comprises supplying fluid to the balloon with a
pneumo-mechanical pump and the at least one parameter of the
balloon is determined by using at least one measurement made by the
pneumo-mechanical pump. In some of these embodiments, the method
further comprises detecting a balloon type for the catheter
inserted into the bodily cavity before inflating the balloon,
wherein the step of determining at least one parameter of the
balloon is based at least partially on the balloon type
detected.
In certain advantageous embodiments, the step of inflating the
balloon comprises supplying fluid to the balloon with an
electro-mechanical pump and the at least one parameter of the
balloon is determined by using at least one measurement made by the
electro-mechanical pump. In some of these embodiments, the method
further comprises detecting a balloon type for the catheter
inserted into the bodily cavity before inflating the balloon,
wherein the step of determining at least one parameter of the
balloon is based at least partially on the balloon type
detected.
In certain advantageous embodiments, the step of inflating the
balloon comprises supplying fluid to the balloon with an
electro-pneumatic pump and the at least one parameter of the
balloon is determined by using at least one measurement made by the
electro-pneumatic pump. In some of these embodiments, the method
further comprises detecting a balloon type for the catheter
inserted into the bodily cavity before inflating the balloon,
wherein the step of determining at least one parameter of the
balloon is based at least partially on the balloon type
detected.
In some embodiments, the step of detecting comprises connecting the
catheter to a balloon identification plate, and connecting said
identification plate to the pump. In certain of these embodiments,
the step of detecting further comprises orienting the
identification plate with a key. In some of these embodiments, the
pump identifies the balloon from the balloon identification plate
electro-mechanically. In other of these embodiments, the pump
identifies the balloon from the balloon identification plate
electro-optically.
In certain embodiments, the pump includes balloon profile data
corresponding to the balloon, and a processor that controls the
supply of fluid to the balloon based at least partially on the
balloon profile data.
In some embodiments, the processor interprets the balloon profile
data and displays a multi dimensional image of the ostium based at
least partially on the balloon profile data.
In some advantageous embodiments, the pump further includes an
imaging system that can translate data from at least one imaging
modality disposed in the catheter.
In certain advantageous embodiments, the processor further
interprets direct and/or indirect imaging data and the
multi-dimensional image of the ostium is based on the direct and/or
indirect imaging data.
In some embodiments, the method further comprises advancing a
distal end of a guide device to a desired location in the paranasal
sinuses before inserting the catheter, wherein the catheter is
inserted into the sinus ostium by advancing the catheter over said
guide device. In some of these embodiments, the method further
comprises removing the guide device from the paranasal cavity
before inflating the balloon.
In certain embodiments, the balloon has an outer wall with a
resecting surface, and the method further comprises repeatedly
deflating and inflating the balloon by supplying fluid to the
balloon in pulsed fashion such that the repeated deflation and
inflation causes the resecting surface to resect biological
material in the sinus ostium. In some of these embodiments, the
biological material comprises polyps. In others, the biological
material comprises tumors. In yet others, the biological material
comprises edematous tissue.
In some embodiments, the method further comprises delivering a
therapeutic and/or diagnostic agent to the ostium via a delivery
lumen of the catheter. In some of these embodiments, the step of
delivering the therapeutic and/or diagnostic agent to the ostium
comprises delivering the agent through at least one opening in the
catheter in fluid communication with the delivery lumen.
In certain embodiments, the method further comprises repeatedly
deflating and inflating the balloon by supplying fluid to the
balloon in a pulsed fashion such that the repeated deflation and
inflation causes the abrading surface to abrade biological material
in the sinus ostium.
In some embodiments, a wall of the at least one balloon has at
least one opening in fluid communication with the delivery lumen
and the step of delivering the therapeutic and/or diagnostic agent
to the biological material comprises delivering the agent through
said at least one opening and inflating said at least one balloon
until it contacts said biological material.
In certain embodiments, the therapeutic and/or diagnostic agent
comprises an antimicrobial agent. In some embodiments, the
therapeutic and/or diagnostic agent comprises an anti-inflammatory
agent. In other embodiments, the therapeutic and/or diagnostic
agent comprises a vasoconstrictor. In yet other embodiments, the
therapeutic and/or diagnostic agent comprises a mucolytic agent. In
further embodiments, the therapeutic and/or diagnostic agent
comprises an anti-histamine. In yet further embodiments, the
therapeutic and/or diagnostic agent comprises an anti-cholinergic
agent. In other embodiments, the therapeutic and/or diagnostic
agent comprises a diuretic.
In certain advantageous embodiments, the catheter includes imaging
markers.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-B are front, partially schematic views of a balloon
catheter system for use with the methods of the invention.
FIG. 2 is a front, partially schematic view of the balloon catheter
of the system of FIG. 1A.
FIG. 3 is a partially cross-sectional view of the deflated balloon
of the system of FIG. 2.
FIGS. 4A-C are enlarged perspective views of an abrading balloon
useful in the catheter system of FIGS. 1A-B.
FIG. 5A shows a method of accessing a maxillary sinus ostium using
a guide catheter.
FIGS. 5B-H are side, partially cross-sectional views of the balloon
catheter of FIG. 1 being operated in the ostium and maxillary sinus
of FIG. 5A.
FIGS. 6A-C are partially exposed, isometric views of the catheter
system of FIG. 1 being operated in a bodily cavity.
FIG. 6D is a partially exposed, isometric view of the catheter
system of FIG. 1 having multiple balloons being operated in a
bodily cavity.
FIGS. 7A-F are side, partially cross-sectional views of the balloon
catheter of FIG. 1 being operated in a bodily cavity.
FIG. 8 is a block diagram illustrating the pneumatics of the pump
of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides improved methods of dilating a
paranasal sinus ostium, removing biological material, and
delivering therapeutic and/or diagnostic agents to tissue in the
nose, nasal cavity or paranasal sinuses of a patient. The methods
comprise inserting a catheter having at least one balloon into a
sinus ostium having an ostial wall; inflating the balloon by
supplying fluid thereto such that the balloon exerts a force on the
ostial wall; determining at least one parameter of the balloon;
establishing an amount the balloon can be inflated without
fracturing the sinus ostium based at least in part on the
determined parameter of the balloon; and dilating the sinus ostium
by inflating the balloon to an amount that does not exceed the
established amount.
The basic components of a balloon catheter system useful in the
methods of the invention are illustrated in FIGS. 1A and 1B. As
used in the description, the terms "top," "bottom," "above,"
"below," "over," "under," "above," "beneath," "on top,"
"underneath," "up," "down," "upper," "lower," "front," "rear,"
"back," "forward" and "backward" refer to the objects referenced
when in the orientation illustrated in the drawings, which
orientation is not necessary for achieving the objects of the
invention.
The system (20) includes a fluid source (22), and balloon catheter
(24) connected to the fluid source (22), to which the fluid source
(22) supplies a fluid, such as a gas, liquid, or mixture thereof.
In an advantageous embodiment, the catheter (24) also includes a
connection port for insertion of an imaging device (29).
Any suitable fluid source may be used in accordance with the
present invention. In the preferred embodiment shown in FIG. 1A,
the fluid source is an electro-pneumatic pump having controls on
the front thereof, from which a physician or assistant can control
the system (as well as a remote control unit). The pump (22)
includes a display (23) to facilitate operation by the physician or
to display multi-dimensional images of the anatomy in vivo. As
shown in FIG. 1B, the fluid source (22) may be a hand or foot
actuated pump having an actuator (27) coupled to a gauge (25) for
monitoring the flow of the fluid and/or pressure of the fluid
delivered to the balloon (30). The fluid may also be provided via a
pneumo-mechanical or electro-mechanical pump.
As shown in FIG. 2, the balloon catheter (24) includes a catheter
(26) made of a polyethylene, or other suitable, material and having
an outer diameter of 1 mm to 20 mm, preferably 2 mm to 14 mm, most
preferably 3 mm to 7 mm, and a length of about 15 to 40
centimeters. A bendable section (28) having a length of about 3 to
12 mm and an angulation of 5 to 45 degrees at the distal end of the
catheter (24) serves as a safety tip. As a result, when the
catheter (24) is inserted into a nasal cavity, it will bend instead
of puncturing the walls of the cavity.
A balloon portion (30) made of polyurethane, silicone, latex,
Yulex, polyethylene, nylon or other suitable material, is located
near the distal end of the catheter (24) or at an otherwise
desirable, predefined distance along the catheter (24). The balloon
(30) comes in a variety of sizes and diameters, which can be
selected to suit the particular application for which the device is
being used. Typically, such balloons will have lengths of 5 mm to
50 mm, preferably 10 mm to 40 mm, and most preferably 15 to 40 mm.
Such balloons will have diameters of 2 to 20 mm, preferably 3.5 mm
to 15 mm, and most preferably, 5 to 7 mm. The pump (22) supplies
the air at a pressure of approximately 2 atmospheres in order to be
able to inflate such balloons to full size, with the particular
value depending on the lumen location. By employing relatively low
pressures that approximate physiologic conditions, the methods of
the present invention have a minimum impact on the physical
structure of the nasal cavities. In particular, the structure of
any polyp or mucous congestion along the walls of the ostium can be
assessed without significant mechanical disruption (as would be the
case with methods that determine wall compliance during high
pressure).
The balloon (30) may include imaging markers (32), such as radio
opaque rings, located at or near the ends thereof. Such markers can
be selected and appropriately positioned in order to reflect the
relevant waves of various imaging modalities in order to allow the
use of such modalities to assist with the precise positioning of
the balloon (30).
The balloon may be covered with a flexible resecting surface, which
may, for example, comprise a fiber mesh affixed to the surface of
the balloon (30). Various textures, such as those described in U.S.
Patent Publication No. 2010/0121270 to Gunday et al., the
specification of which is incorporated herein by reference in its
entirety, may be utilized in the methods of the invention.
Alternatively, the balloon may be covered with surface protrusions
to abrade bodily tissues. The abrasion of the bodily tissues
perpetuates fluid extravasation processes and stimulates associated
cellular absorption of the diagnostic and/or therapeutic agents
into the adjacent tissues. The textured outer surface of the
balloon can also act as a gripping surface for attachment to bodily
tissues.
FIGS. 3 and 4A-C show protrusions (41) on the surface (43) of
balloon (30), which may be formed by a fiber mesh affixed to the
surface (43) of the balloon (30) during the molding process, that
optimize the abrasion capability of the balloon (30). The fiber
mesh may be made of lycra, polyurethane, composite springs, or
other appropriate material. In other advantageous embodiments,
dimensional surface structures or inflatable sinuses that are
encapsulated in the surface substrate (43) of the balloon (30) may
be used to produce the surface protrusions (41).
The protrusions (41) forming the abrasive surface of the balloon
(30) can have various shapes and configurations, depending on a
particular application. For example, as shown in FIG. 4A, the outer
surface (43) of the balloon (30) has outwardly extending
protrusions (41) that form a lattice-like structure on the surface
of the balloon (30). In another advantageous embodiment shown in
FIG. 4B, the protrusions (41) are in a form of dimples that extend
outwardly from the outer surface (43) of the balloon (32). In yet
another advantageous embodiment illustrated in FIG. 4C, the
protrusions (41) form a spiral-like pattern that extends
circumferentially on the outer surface (43) of the balloon (30). It
should be noted that any other shapes and configurations of the
surface protrusions can be used in accordance with the present
invention.
It is also advantageous, when using an abrading balloon, to include
at least one opening (39) in the catheter (26) positioned on either
side of the balloon (30). The opening (39) is in fluid
communication with a delivery lumen (61) within the catheter (26)
to supply a therapeutic and/or diagnostic agent. It should be noted
that in some embodiments, the wall of the balloon (30) may have at
least one opening therethrough, and the delivery lumen (61) is used
to supply the therapeutic and/or diagnostic agent to the chamber
(37), which is then delivered to biological material through the
openings in the balloons outer surface (43).
Referring back to FIG. 2, the balloon catheter (24) includes an
inner lumen breakout Y junction (40) to facilitate the introduction
of a guide wire, air bypass, drug delivery, or visualization
conduit. The proximal end of the inner lumen (42) after Y junction
(40) is terminated with a luer connector (44). The outer lumens are
terminated at their proximal end with a keyed connector (46), which
includes a key (48) and a balloon identification plate (50).
The Y junction (40) serves several purposes. First, it brings out a
separate, inner lumen (42) of the catheter (24) to a suitable
connector, such as the aforementioned luer connector (44), in order
to provide an independent passage. Additionally, the Y junction
(40) also includes a shut-off valve (not shown) for stopping the
balloon (30) from deflating. This may be used, for example, when it
is required to leave the inflated balloon in place for a lengthy
period of time in order to treat chronic bleeding.
As noted above, the catheter (24) is terminated at the proximal end
with a keyed balloon identification plate (50). The purpose of this
connector is to electronically detect the catheter (24) when it is
inserted into the pump (22) and to identify the particular type of
balloon catheter being used. The key (48) orients the connector
(46) and the identification plate (50) in such a way that the
balloon type can be identified by the pump (22) using
electro-optical or electro-mechanical means.
Each type of balloon (30) that can be used with the pump (22) is
characterized, and balloon profile data is registered in lookup
tables. By identifying the type of balloon (30) that is connected
the pump (22), the appropriate profile data can be retrieved and
used to ensure that the appropriate pressure, volume, flow, and
timing adjustments can be made to safely and effectively operate
the balloon (30). The balloon profile data contained in the lookup
table, along with appropriate pressure and flow measurements (as
further discussed below), allows one to make biological material
density approximations. This balloon profile data, along with
approximated lumen (ostium or sinus) diameter, biological material
density, as well as any user commands, are used to adjust the
amount of gas the pump (22) delivers to the balloon (30) in order
to achieve the desired inflation and deflation amounts.
Referring to FIG. 3, the inner lumen (42) is used as a means for
accurately positioning the balloon catheter (24) as a conduit for a
guide wire (63) when inserting the deflated balloon catheter (24)
into the bodily cavity. The outer lumen (60) of the catheter (26)
is used to inflate and deflate the balloon (30) through the holes
(62) provided in the catheter's outer walls (64). The outer lumen
(60) is blocked at the distal end of the balloon (30) so that air
intended for inflation and deflation will not escape.
In certain advantageous embodiments, delivery lumen (61) and holes
(64) are used to deliver, for example, a medicinal drug when used
in conjunction with a balloon (30) having abrading protrusions
(41). The lumen (61) and holes (64) can be used to deliver any
number of things to assist with opening the cavity, circulation,
aspiration, respiration, assisting the decomposition of an
obstruction, or stimulating healing in the affected area, including
air, aspirates, drugs, biologics, biogenetic agents,
nano-particulates, solutions, stem cell and gene therapies, and
stents and scaffolds. Examples of diagnostic or therapeutic agents
are contrast agents, a pharmaceutically acceptable salt or dosage
form of an antimicrobial agent (e.g., antibiotic, antiviral,
anti-parasitic, antifungal, etc.), an anesthetic agent, an
analgesic agent, a corticosteroid or other anti-inflammatory (e.g.,
an NSAID), a decongestant (e.g., vasoconstrictor), a mucous
thinning agent (e.g., an expectorant or mucolytic), an agent that
prevents of modifies an allergic response (e.g., an antihistamine,
cytokine inhibitor, leucotriene inhibitor, IgE inhibitor, or
immunomodulator), an allergen or another substance that causes
secretion of mucous by tissues, anti-proliferative agents,
hemostatic agents to stop bleeding, cytotoxic agents (e.g.
alcohol), biological agents such as protein molecules, stem cells,
genes or gene therapy preparations etc.
Antimicrobial agents can include, but are not limited to,
acyclovir, amantadine, amikacin, gentamicin, tobramycin,
amoxicillin, amphotericin B, ampicillin, sulbactam, atovaquone,
azithromycin, cefazolin, cefepime, cefotaxime, cefotetan,
cefpodoxime, ceftazidime, ceftizoxime, ceftriaxone, cefuroxime,
cefuroxime axetil, cephalexin, chloramphenicol, clavulanate,
clotrimazole, ciprofloxacin, clarithromycin, clindamycin, dapsone,
dicloxacillin, doxycycline, erythromycin, fluconazole, foscarnet,
ganciclovir, atifloxacin, imipenem, cilastatin, isoniazid,
itraconazole, ketoconazole, metronidazole, nafcillin, nystatin,
penicillin, penicillin G, pentamidine, piperacillin, rifampin,
quinupristin-dalfopristin, ticarcillin, trimethoprim,
sulfamethoxazole, tazobactam, valacyclovir, vancomycin, mafenide,
silver sulfadiazine, mupirocin, nystatin, triamcinolone,
butoconazole, miconazole, tioconazole, and combinations
thereof.
Anti-inflammatory agents can include, but are not limited to,
beclomethasone, flunisolide, fluticasone proprionate, triamcinolone
acetonide, budesonide, loterednol etabonate, mometasone,
aclometasone, desonide, hydrocortisone, betamethasone,
clocortolone, desoximetasone, fluocinolone, flurandrenolide,
prednicarbate, amcinonide, desoximetasone, diflorasone,
fluocinolone, fluocinonide, halcinonide, clobetasol, salicylic acid
derivatives, aspirin, sodium salicylate, choline magnesium
trisalicylate, salsalate, diflunisal, sulfasalazine, olsalazine,
acetaminophen, indomethacin, sulindac, tolmetin, dicofenac,
ketorolac, ibuprofen, naproxen, flurbiprofen, ketoprofen,
fenoprofen, oxaprozin, mefenamic acid, meloxicam, piroxicam,
meloxicam, nabumetone, rofecoxib, celecoxib, etodolac, nimesulide
and combinations thereof.
Exemplary decongestants include, but are not limited to,
pseudoephedrine, xylometazoline, oxymetazoline, phenylephrine,
epinephrine, and combinations thereof.
Mucolytic agents can include, but are not limited to,
acetylcysteine, guaifenesin and combinations thereof.
Anti-histamines can include, but are not limited to, cromolyn,
nedocromil, azelastine, diphenhydramine, loratidine, and
combinations thereof.
An exemplary anti-cholinergic is ipratropium bromide.
Diuretics can include, but are not limited to, furosemide and/or
hyperosmolar agents such as sodium chloride gel or other salt
preparations.
In certain applications, it may be desirable to locally deliver in
a similar manner agents that will facilitate photodynamic therapy.
Likewise various forms of energy can be delivered locally,
including laser, microwave, RF, cryogenic, and thermal
energies.
In certain embodiments, the balloon catheter can include a
multi-balloon construct at its distal end. This construct may
include, for example, a proximal balloon segment, a center balloon
segment, and a distal balloon segment as described in U.S. Patent
Publication No. 2010/0121270 to Gunday et al., incorporated herein
by reference. In this way, with the proximal and distal balloons
remaining inflated, the drug is contained in the targeted site and
evenly distributed as biological material is resected or
abraded.
In a preferred embodiment, the openings (39) are used to
accommodate the imaging device (29), which extends out of the
opening (39) to view surrounding tissue during the insertion of a
multi-balloon catheter into the bodily cavity.
Additionally, in some of the multiple-balloon embodiments, the
above-described imaging markers (e.g., radio opaque rings), can be
located at or near the ends of each balloon segment in order to
facilitate the use of certain imaging modalities to assist with the
precise positioning of the balloons.
A method for operation of the balloon catheter system (20) for
dilating ostia can be generally described with reference to FIGS.
5A-H. FIG. 5A shows a method of accessing a maxillary sinus ostium
(51) using guide catheter (52). Guide catheter (52) is introduced
through a nostril and advanced in the paranasal anatomy such that a
safety tip (54) is located inside or adjacent to a maxillary sinus
ostium (51). The catheter (52) is flexible and steerable or
pre-shaped such that a proximal bent, curved, or angled region
allows guide catheter (52) to be positioned around the inferior
turbinate and the middle turbinate.
As shown in FIG. 5B, a guidewire (63) or a suitable diagnostic or
therapeutic device may then be introduced through the lumen of
guide catheter (52) into the maxillary sinus (56). In some
embodiments, the guidewire (63) includes a balloon (53) which is
inflated once in the maxillary sinus to anchor the guidewire in
place.
Referring to FIG. 5C, after a visual inspection via an endoscope,
CT-scan, x-ray, or other anatomical mapping means, a balloon
catheter (24) is selected, and the deflated device is inserted into
a nasal passage until the balloon (30) is positioned in the desired
ostium. This may be accomplished by inserting the proximal end of
the guidewire (63) into a lumen of the catheter (24) and sliding
the catheter (24) over the guide wire (63). The balloon (53) is
then deflated, and the guidewire (63) is pulled out through the
inner lumen of the catheter (24). The balloon catheter (24) is
connected to a pump (which is further described in detail below),
at which time the pump determines the type of balloon catheter that
has been inserted. The pump may render a multi-dimensional image of
the anatomy in vivo on the display based on the balloon profile
data alone or in concert with direct and/or indirect imaging
methods and imaging guidance.
Referring next to FIG. 5D, the balloon (30) is inflated by the pump
(which knows the type of balloon to which it is connected) at an
air pressure of approximately 2 atmospheres for a fixed amount of
time, and the flow is measured (after the physician presses an
inflate button on the pump). Each "inflate" command will inflate
the balloon by an incremental amount based on the type of balloon
that is connected. This incremental inflation is accomplished by
opening an inflate valve for a set amount of time while a deflate
valve remains closed. In this way, the balloon is inflated to the
size desired by the user. Alternatively, pressing and holding the
inflate button will inflate the balloon in a continuous
fashion.
While inflating, the flow of gas (ml/sec) is measured. After
closing the inflate valve, the balloon pressure is measured, and an
approximation of the volume V is made based on the ideal gas law
(V=nRT/P) and a lookup table, which contains balloon
characteristics and universal constants. Here, T is assumed
constant at 310.degree. K (body temperature can be measured and
entered into the equation as well), R is a gas law constant, n is
moles of gas, which is proportional to the measured flow, and P is
the measured pressure. With each incremental inflation, V is
recalculated, and the relative volume change (V2-V1) is displayed.
Knowing the shape of the balloon from the balloon identification,
and using the data from the lookup table, the relative change in
balloon diameter (D2-D1) is also calculated and displayed. On the
basis of information obtained during this step, the balloon
catheter (24) may be repositioned, and this repeated, if
necessary.
Thereafter, as shown in FIGS. 5E-F, the balloon (30) is further
inflated such that it exerts a force on the ostial wall, thereby
dilating the ostium (51). As the pump is operated, data from the
measurements and calculations is continuously updated and
displayed. Based on the determined pressure and/or other parameters
noted above and any predetermined threshold values set in the pump
(e.g., a maximum balloon pressure), the pump continues to supply
the balloon with fluid until it reaches an amount less than that
which would cause the sinus ostium to fracture. When the diameter
of the ostium (51) has been dilated to the maximum diameter, the
balloon is deflated and removed from the lumen (51). As shown in
FIG. 5G-H, optionally, it may be desirable to push the deflated
catheter into to the sinus (56) beyond the ostium (51), and
reinflate balloon (30) to push any fluid out of the sinus through
the now widened ostium (51).
A method for operation of the balloon catheter system (20) for
delivering a therapeutic and/or diagnostic agent to biological
material in the nose, nasal cavity or paranasal sinuses can be
generally described with reference to FIGS. 6A-C. Although shown
delivering agents to a target biological material (53), the method
can also be used for delivering agents into a sinus, i.e. the
maxillary sinus.
Referring to FIG. 6A, after a visual inspection via an endoscope,
CT-scan, x-ray, or other anatomical mapping means, a balloon
catheter (24) having abrading protrusions (40) is selected, and the
deflated device is inserted into the nasal cavity with the balloon
(30) positioned adjacent to the target biological material (53).
This may be accomplished by using a guide catheter (52) and a guide
wire (63), as previously noted. The balloon catheter (24) is
connected to a pump, at which time the pump determines the type of
balloon catheter that has been inserted.
As shown in 6B, the balloon (30) is then inflated by the pump as
previously described. This causes the abrasive outer surface (41)
to contact the biological material (53) and creates surface
abrasions in the biological material. The surface abrasions act to
create capillary blood flow and to instigate flow of white blood
cells to the biological material, which facilitates absorption of
an agent into the biological material. The pressure regulator and
flow meter along with the known dimensions of the balloon provide
feedback to the pump necessary to determine dimensions and
resistance of the biological material from which a determination is
made as to the diameter of the ostium and the density of the
biological material. Using theses parameters, the microcontroller
makes the appropriate pressure and timing adjustments necessary to
maximize the effectiveness of the balloon, provide the physiologic
metrics of the affected and non-affected areas, and provide data
points and indicators related to the specific dimensional and
density characteristics of the intra-ostial anatomy and pathology
and aid the physician in safely determining and delivering
treatment.
The balloon (30) can be sequentially pulsed to create further
surface abrasions. When a pulse button on the pump is pressed, the
balloon (30) is deflated and inflated in a cyclical fashion, based
either on parameters that were entered by the user, or on default
parameters selected by the pump, which are based on the
characteristics of the particular balloon (which has been
identified as a result of the aforementioned balloon identification
plate) and the diameter and/or density measurements made by the
system. In this way, the pulse mode of the pump causes the balloon
to pulsate according to a desired frequency or change in volume
within the balloon, producing a periodically recurring increase and
decrease in balloon size.
A therapeutic and/or diagnostic agent is then delivered via the
openings (39) in the catheter (26), as shown in FIG. 6C. It should
be noted that the agent can also be delivered through a plurality
of openings provided in balloon (30). As the agent is delivered, it
coats the outer surface of the balloon (30). The balloon (30) is
inflated, such that the outer surface of the balloon contacts the
biological material (53), and is kept that way for a desired period
of time. The balloon (30) is then at least partially deflated,
recoated with the agent, re-inflated and kept that way again. This
sequential and/or constant expansion of the balloon (30) instigates
extravasation and initiates fluid extravasation through the vessel
walls and into the adjacent biological material.
In a multi-balloon construct (57), as shown in FIG. 6D, the
proximal balloon (58) can be independently inflated to create a
drug delivery chamber to contain the agent and aid the volumetric
pressure requisite to the extravasation of the agent into the
submucosal tissues and sinus.
In an advantageous embodiment, an imaging device disposed in one of
the lumens of the catheter (26) is used to help position the
balloon at the proper location. Preferably, the imaging device
extends out of the opening (39) in the catheter (26), such that the
tissue in front of the catheter can be viewed by the imaging device
during the insertion of the multi-balloon catheter (57) into a
bodily cavity.
Once the agents have been delivered and extravasted into the
biological material at the target site, any remaining agent can be
evacuated via the same openings (39) and lumens through which they
were supplied using suction. In certain advantageous embodiments,
the pump provides a negative pressure to vacuum out the agents. The
various lumens and corresponding openings (39) can be used to
cyclically deliver and evacuate the agents and various other fluids
instantly, sequentially, intermittently and/or continuously over
designated time intervals.
The operation of the balloon catheter system (20) for resecting
polyps or other undesirable biological material (55) from the nose,
nasal cavity or paranasal sinuses can be generally described with
reference to FIGS. 7A-F. Referring first to FIG. 7A, after a visual
inspection via an endoscope, CT-scan, x-ray, etc., a balloon
catheter is selected, and the deflated device is inserted into
position in a bodily cavity. This may be accomplished by using the
working channel of an endoscope and guide wire, as previously
noted. The catheter is connected to the aforementioned pump.
Referring next to FIG. 7B, the balloon is inflated by the pump and
the pump calculates the initial approximation of the biological
material density and the size of the opening in which it is
located, and displays the results for confirmation by the
physician. As shown in FIGS. 7C-D, when a pulse button on the pump
is pressed, the pump causes the balloon to pulsate according to a
desired frequency or change in volume within the balloon, producing
a periodically recurring increase and decrease in balloon size.
Accordingly, the resecting surface of the balloon repeatedly comes
into contact with the biological material to create micro-impacts
thereon. As the balloon is deflated and inflated, the resecting
surface creates just enough interference fixation, concentrically,
along with compressive force excitation and friction upon the
unwanted biological material, to promote compressive force
exhaustion and abrasion to elicit the decomposition and excision
thereof, such that the targeted biological material is resected in
a non-traumatic way. As the biological material is destroyed and
removed, the balloon is inflated to a larger starting diameter and
these steps are repeated until all the unwanted biological material
is resected.
Meanwhile, the pump continually monitors the balloon pressure and
gas flow, and it updates a graphical display accordingly. This
gives the physician an indication as to when to stop the pulse mode
and evacuate the loosened biological material.
Referring to FIG. 7E, once the obstruction is broken up, the
balloon is deflated (by pressing a deflate button on the pump), and
the balloon is inserted further distally into the bodily cavity,
past the location of unwanted biological material.
A shown in FIG. 7F, the balloon is then re-inflated (by pressing
the inflate button on the pump) and gently pulled towards the
proximal end, bringing with it the loose biological material and
debris to a point where it can be removed using forceps or suction.
In a multi-balloon construct, the debris can be removed through one
of the available lumens.
While the resecting and abrading have been described with respect
to the pulsation mechanism of action described herein, such action
is not exclusive. That is, other mechanisms of action may be
employed in addition to pulsation as needed, such as linear
translation of the balloon along the catheter, as well as rotation.
These motions are particularly useful in mucosa resection.
A pump (22) that controls the operation of the balloon (30)
described above will hereafter be described. FIG. 8 represents a
block diagram of the pneumatic components and operation of the
pump. The pump includes an air compressor (232) and a pressure tank
(233), such as a Festo model CRVZS-0.1, which enable it to achieve
up to 10 atmospheres of continuous pressure. The air pressure in
the tank (233) is continuously monitored by a microcontroller
(254). The microcontroller initiates the compressor (232) to
operate via an electrical signal output (253) when the tank
pressure drops below 4-5 atmospheres. The size of the tank (233) is
selected such that at least one procedure can be completed without
the compressor operating. The microcontroller calculates and
displays the amount of air in the tank (233), which indicates to
the user whether there is enough air to complete the procedure. A
check valve (234), such as a Festo model H-1/8-N1, is located
between the compressor (232) and the tank (233) in order to prevent
the pressured gas from flowing back into the compressor (232). In
another variation of the pump (22), however, the above-referenced
compressor and pressure tank are not included, and the pressurized
air or carbon dioxide is instead provided from an external source,
such as a hand actuated pump, CO.sub.2 cartridge, gas tank or the
operating room walls commonly found in an operating room.
The pressurized gas from the air tank (233) first goes through a
pressure regulator (238), which is electronically controlled via an
analog electrical output (0V-10V) signal (246) generated by the
microcontroller to supply air to the balloon at an exact pressure,
which can be set and changed by the physician. However, any
pressures higher than the upper limit for the particular balloon
being used will generate a warning signal. As explained above,
different balloon catheters may be used depending on the
application, which are identifiable via key connectors. Therefore,
pressure, volume, and flow characteristics of different types of
balloons are contained in lookup tables in order to optimize the
operation of the balloons and to ensure their consistent
performance.
Accordingly, when the pressure is set higher than the balloon's
upper limit, the detection of gas flow will cause the pump to stop
and produce the warning, and the physician must then take a
specific action to override this condition. Similarly, if there is
no balloon pressure, the detection of gas flow will also generate a
warning, as this may mean the balloon has ruptured. It should
further be noted that the pump will also not operate if a catheter
is not connected. Additionally, a balloon's operation when first
removed from the packaging may vary from its normal operation,
requiring that they are first exercised before use in the body.
Therefore, the setup and preparation function of the pump allows
for this variance.
In certain advantageous embodiments, a vacuum source (239), such as
a Festo model VN-05-L-T3-PQ2-VQ2-R01-B, is also included in the
pump so that the balloon can be rapidly deflated in a consistent
manner. This component also aids in achieving higher frequencies
during the pulse mode of operation. The vacuum source (239) is
turned on and off by the microcontroller via an electrical output
signal (247).
Two microprocessor-controlled solenoid valves--a deflation valve
(240) and an inflation valve (241)--are used to control the
inflation and deflation of the balloon. The appropriate balloon
inflation size is achieved by keeping the gas pressure constant,
using the balloon pressure, flow, and volume characteristics from
the lookup table data, and timing the on/off activation periods of
the valves (240, 241). Deflation valve (240) and inflation valve
(241) are controlled by a deflate electrical signal (248) and an
inflate electrical signal (249), respectively, which are generated
by the aforementioned microcontroller.
The gas pressure is continuously monitored by the microcontroller
using pressure regulator (242) at the input from the tank (233), a
pressure regulator (243) at the output of the regulator (238), and
pressure regulator (244) at the output to the balloon. These
pressure regulators, which may be, for example, Festo model
SDET-22T-D10-G14-U-M12, provide to the microcontroller analog
electrical signal (0V-10V) inputs (250, 251, 252) that vary
proportionally to the pressure at the regulators (242, 243, 244).
The gas passes through an electronic flow meter (245), such as a
Festo model SFET-F010-L-WQ6-B-K1, and a filter (246), before being
delivered to the balloon. The flow meter (245) provides an analog
electrical signal input (254) to the microcontroller that indicates
the amount of gas flow to the balloon.
The pressure regulator (244) and flow meter (245), along with the
known dimensions of the balloon, provide the feedback necessary to
determine the ostial wall or biological material dimensions and
resistance via circumferential force and depth resistance, from
which a determination is made as to the ostial diameter or the
density of the biological material. Using these parameters, the
microcontroller makes the appropriate pressure and timing
adjustments necessary to maximize the effectiveness of the balloon,
provide the physiologic metrics of the affected and non-affected
areas, and provide data points and indicators related to the
specific dimensional and density characteristics of the intra-lumen
anatomy and pathology to aid the physician in safely determining
and delivering treatment.
In this way, the gas pressure is strictly monitored and maintained
at 2 atmospheres in order to keep the balloon from bursting. The
high gas input pressure (up to 10 atmospheres) is reduced to and
regulated at 2 atmospheres electronically and under software
control. However, the pressure delivered to the balloon can be
increased or decreased under certain conditions via operator
commands.
A further explanation of the components and operation of the pump
(22) is provided in the aforementioned U.S. Patent Publication No.
2010/0121270 to Gunday et al.
Alternatively, one can use a handheld apparatus to measure the
relative level of ostial deformation without fracturing the ostium.
For example, one could use a ball pump that remains outside of the
body and is connected to the balloon, which includes a pressure
gauge. The measurements can be collected by sequential inflation of
the balloon using the pump. Alternatively, the device could include
transducers at the distal end of the catheter or on balloon, and it
may display its measurements as a digital readout. In other cases,
an instrument such as a tenaculum could be used to slowly open and
control/measure the ostium. The hand actuator can employ a CO.sub.2
cartridge in the actuator and be used in conjunction with a mobile
device application (e.g., iPhone app), to measure pressure and
volume.
Although the above described methods are described with reference
to the sinus ostia, the methods of the present invention are
suitable for transnasal dilation of other passageways in the ear,
nose and/or throat, such as the Eustachian tube and nasolacrimal
duct.
It should be understood that the foregoing is illustrative and not
limiting, and that obvious modifications may be made by those
skilled in the art without departing from the spirit of the
invention. Accordingly, reference should be made primarily to the
accompanying claims, rather than the foregoing specification, to
determine the scope of the invention.
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